AN23.1-6 | Mediastinum — Part 3

SELF-CHECK

A. Posterior to the lung hilum

B. Lateral surface of the pericardium

C. Between oesophagus and trachea

D. Along the azygos vein

CLINICAL PEARL

Pancoast tumour (superior sulcus tumour at the lung apex) can compress:
- Sympathetic chain → Horner's syndrome (ptosis, miosis, anhidrosis)
- Brachial plexus (C8, T1) → wasting of intrinsic hand muscles + ulnar border pain
- Subclavian vessels

This triad — Horner's + hand weakness + shoulder pain — in a smoker is a Pancoast tumour until proven otherwise.